Apparatus for handling gases and vapors



Dec. 8, 1925- 1,564,288

c. G. SMITH APPARATUS FOR HANDLING GASES AND VAPORS Filed Aug. I0, 1922 wfii z/esa I v 50 M wmz Patented Dec. s, 1925.

CHARLES SMITH, OF MEDFORD, MASSACHUSETTS, ASSIGI IOR TO RAYTHEON MANU- sAo'rU-Rruc COMPANY, MASSACHUSETTS.

F CAMBRIDGE, MASSACHUSETTS, A CORPORATION OF APPARATUS non HANDLING eases aunvnrons. v

' Application filed August 10, 1922. Serial No.- 530,923.

To all 1071 am it may concern:

Be it known that I, CHARLES G. SMITH, a citizen of the United States, residing at Medford, in the county of Middlesex and State of Massachusetts, have invented certain new and'useful Improvements in Apparatus for Handling Gases and Vapors;

and I do hereby declare the following to bc a full, clear, and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same. 1

The present invention relates to apparatus for handling gases and vapors and more particularly to apparatus .of this type employed for refrigerating purposes.

The application of Smith Serial No. 562,- 232, filed May'19, 1922, discloses a refrigerating apparatus in which the flow or circula tion of the refrigerating medium 'is accomplished in a new and novel manner. According to this application, the refrigerating medium is maintained at a relatively low absolute pressure in the evaporation chamber and is pumped to the condensing chamber through a, molecular gas pump, which derives its energy from a suitable source of heat. This gas pump may consist of one or more stages having properly spaced and insulated hot and cold surfaces designed to divide the pump into different,

regions. From the pump the liquid vapor or gas passes into a chamber in which it is condensed to. a liquid and the resultant heat is dissipated in any suitable manner. From the condensing chamber the condensed liquid is returned to the evaporation chamber and the cycle of operations is repeated. It will be evident to those skilledin the art that only dissipating the heat withdrawn by the evaporation of theliquid from the space to be refrigerated but in addition of dissipating the-heat energy which is supplied to the gas pump and not converted into useful work.

It is accordingly an object ofthe present invention to improve apparatus of this-character in such a manner that the efficiency of the apparatus is increased and the dissipation of heat facilitated. v

A further object of the invention is to improve and, increase the general efiiciency of a gas pump of this genera] type and more pressure.

such an apparatus must be capable of not.

particularly sucha pump comprising a plurality of stages.

With these obj ectsin viewthe several features of the invention consist. in certain novel features of construction, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be obvious tothose skilled in the art from the following description;

In the accompanying drawing, Fig; 1 illustrates a View in elevation of a refrigerating apparatus'embodying the features of the present invention, and Fig. 2 is a detail view, with parts broken away, diskshereinafter described.

The gas or vapor pump shown in the illustrated embodiment of the invention comprises essentially a series of hot surfaces indicated at 10 with a series of'coldor relatively cooler surfaces indicated at 12. As'described in the'application hereinbefore re of the ferred to, the provision of these hot-and cold surfaces properly spaced with relation to general movementof the gas or liquid vapor upwardly and at a progressively increasing rating the cold and hot surfaces is insulated in a manner to prevent any substantial transfer of heat ther'ebetween, as fully explained in the application hereinbefore referred to. The hot surfaces may consist of a series of relatively .thinmetallic disks with suitable openings, the disks projecting radially from the outerperipheryof a tube parted to the walls of the tube 15 it may flow outwardly through the material of the connected disks, retaining the surfaces at the desired temperature. I This heat energy is supplied, as indicated, by an electric heating coil 18 received within the tube or by any-other convenient source of heat energy, such as ages flame. The opposing cold surfaces may be constituted by a series of similar disks extending inwardly from the The'r'ela-tively small space sepa- '15 of conducting material. If heatis imfrom the outer shell to preventany direct transfer of heat by metallic conduction therebetween. The evaporation chamber-0f the apparatus is indicated at 22 and the condensing chamber at 24, the two chambers being connected through. the several stages of the gas pump, These chambers are hermetically sealed from the outer'atmosphere by the casing 26 and have no connection with the interior of the heating tube 15. The re-.. frigerating chamber 22 contains a refrigerating liquid, indicated at 30,. of'rela-tively' impact therewith. By suitably coordinating the openingsor passages through the hot and cold surfaces with the mean free path of the molecules at any given pressure of the gas, any-substantial movement of the molecules in a direction opposite to the direction of rebound is precluded. A generalmovementof molecules in the. desired direction is initiated in certain of the regions of convection, the molecules passing from one region into-the next, where additional energy is imparted. It will be evident that this opera-- tion may be carried out with one or more stages of the'pump. 1

It isdesirable in apparatus of this character to facilitate the dissipation of heat from the apparatus and to this end the present invention contemplates more particularly a new and improved method of accomphshmg this result through the employment of the condensed refrigerant. To this' end the outer'periphery of the molecular pump is enclosed by a funnel shaped wall 32 which graduallv tapers inwardly from the first to the last stage of the pump in such a manner that the effective area of the first stage is' materially greater than the effective area of the last stage of the pump. This wall con-.

sists of material which conducts heat freely and in conjunction with the outer casing provides a liquid containing receptacle or trough 34 in which the condensed refrigerating liquid is collected. The cold disks or plates 72 are connected-directly to the wall 32 and serve to conduct heat to the wall. This heat'is transferred to the condensed liquid 34 and the latter being at a relatively low absolute pressure boils or evaporates when an excessof heat is supplied. 'This secondary evaporation of the liquid serves to abstract relatively large quantities of heat' from the liquid and the surrounding walls and the vapor produced thereby rises in a condensing chamber 2.4; and is condensedhn the wallsin the usual manner, this heat be ing dissip'atedthrough the usual conducting fins-36 projecting outwardly from the casing, or by some equivalent form of construction. The condensed vapor or gas is returned from the wall of the condensing chamber to the space 34, an annular trough 40 serving to collect liquid which may have ,conden'sed on the wall of tube 15. A return pipe 42 passing d wnwardly from the space 3410 the evaporation chamber serves to re- ;turn the liquid to the evaporation chamber,

the pipe 42 being provided with a trap 44 at the lower end, as indicated. Thisforin of construction greatly increases the ability of the apparatus to dissipate heat, more especially heat from-the molecular pump. It. will be evident that with thisconstruction' the waste heat from the pump is easily conveyed to the condensingchamber, where an ample radiating surface may be provided for its dissipation, making it unnecessary'to dissipate this heat entirelyfrom the walls I surrounding the 'pump or by conduction through the materialof the walls from the region surrounding the pump, to the condensing region. he provision of this means for dissipating the heat furthermore permits the outer casing to'be formed of amaterial which may be a relatively. poor conductor of heat and thus insures, that the amount of heat passing through the walls-by .condu'c -fl tion from the condensing region to the evaporation region will be negligible. ,As thepressure of the gas in successive stages "of the pump increases, the effective area of hot surface required for the insulation. of the gas is less and the provision of the tapering .funnelshaped wall of the molecular pump provides a simple and convenient method of reducing this cross section. As indicated 1n the drawings, the molecular pump gradually decreases 1n effective area throughout successive stages. I clalmz e 11b; ii;

1.. In apparatus of the character described, means including a pair of members -at different temperatures and in spaced relation to-each otherfor pumping a gaseous medium in response. to said temperature difference, means whereby said member of j higher ten'iperature is heated, and means for supporting'a cooling liquid in heat transfer relation to sald member of lower tempera.-'

ture.

2; In apparatus of the character described, means for pumping agase'ous mediam in response to a temperature difference between separate portions thereof, a source of heat for said portion of higher tempera ture, and means for supporting ava'porizs able cooling liquid inheat transfer relation to said portion of lower,temperature.-

3. In' apparatus of the character debetween separate portions thereof, a source her and means including a pair of members i of heat for said portion of higher temperature, means for supporting a vaporizable cooling liquid in heat transfer relation to said portion of lower temperature, and

means for condensing the vaporizable liquid and returning the condensed liquid to its position in heattransfer relation to said portion of lower temperature.

4. In apparatus of .the character described, means for pumping a gaseous medium in response to a temperature differencebetween separate portions thereof, a source of heat for said portion of higher temperature, an evaporation chamber at the lower pressure side of said pumping means, and means for condensing vapor propelled through said pump from said evaporation chamber and depositing the condensed liquid in heat transfer relation to said portion of lower temperature to cool said portion.

5. In apparatus of the character described, stationary means for pumping a gaseous medium in response to a temperature difference between portions thereof and means whereby said difference in temperature is maintained, including a source of heat for said portions of higher temperature, and means for supporting a cooling liquid in heat transfer relation to said portion of lower temperature.

6. In apparatus of the character described, an evaporation chamber, a condensing chamat different temperatures and in spaced relation .to each other for pumping a gaseous medium for said evaporation chamber to said condensing chamber in response to the said temperature differences, means whereby said member of higher temperature is heated, and means for receiving and collecting ing a wall in heat transfer relation to one of said members, andmeans Within said' container for supportingthe cooling liquid in heat transfer relation with one of said members. p

9. In apparatus of the character described, meansdncluding a pair of members at different' temperatures and in spaced relation to each other for pumping a gaseous medium in response to said temperature difference, acontalner for sealing said pumping means from the atmosphere, said container having a wall in heat transfer relation to one of said members and having a recess, the

wall of which is in heat transfer-relation to the other of said members, a heating element in heat transfer relation to one of said walls, and means for supporting a cooling liquid in heat transfer relation to the other of said walls. I

10. In apparatus of the character described-,meansincluding a pair of membersat difiierent temperatures and in spaced relational to each otherfor pumping a gaseous medium in response to said temperature dif' ference, a container for sealing said pumping means from the atmosphere, said container having a wall in heat transfer relation to one of said members and having a recess, the wall of which is in heat transfer relation to the other of said members, a heating element in said recess to transmit heat to the wall thereof, and a cooling liquid in heat transfer relation to the other of said members.

11. In apparatus of the character described, a fluid passageway, 'hot and cold surfaces disposed transversely of said passageway at-spaced intervals'and facing in opposite directions, av passage available for the movement of gas molecules past said surfaces, the width of said passage being comparable to themean free path of the liquid from the condensing chamber in heat v transfer relation to said member at lower temperature for cooling said member.

' in said container for supporting a cooling liquid in heat-transfer relation to said member of lower temperature.

. 8. In apparatus of the character described, means including a pair ofmembers at dif ferent temperatures and in spaced relation to each other for pumping a gaseous medium in response to sald temperature differences,

a container for sealing said pumping means from the atmospheraisaid container hav- 'at spaced intervals, oppositely directed surgas molecules, and means forsupporting a cooling liquid in heat transfer relation to said cold surfaces.

12. Apparatus of the character described having a fluid passageway, perforated plates disposed transversely of said passageway at spaced intervals, oppositely directed surfaces of recurrent plates having greater.

ability to interchange heat withthe fluid than the other surface of thesame plates,

and means associated with'th'e latter S111;

face for bringing a liquid .into heat-conduc- -'tive relationship thereto.

13. Apparatus of the character described having a fluid passageway, perforated plates disposed transversely of said passageway faces of recurrent plates having greater ability tointerchange heat with ,the fluid than the other surfaces ofthe same plates, and means whereby certain of the plates may be heated, and means whereby certain 'other of the plates may be cooled by a circulating liquid.

.v heat/with the fluid on one side, and another set of recurrent plates having greater ability to interchange heat with the'fluid on the opposite side, and means whereby one set of plates may be heated and means whereby the otheriset of plates may be cool'edby a circulating fluid 1n heat conducting rela -ti0nshi thereto.

15; pparatus of the character describedhaving a fluid passa eway, perforated plates disposed transverse y of said passageway I at spaced intervals, one surface of each late having greater abilityto interchange ieat withthe fluid'than the other surface, and

a liquid in heat conducting relationship-to the latterof said surfaces. 7

' CHARLES G. SMITI-L 

